Ergonomics is a systems-oriented discipline which now applies to all aspects of human activity. The term ‘system’ in IEA’s definition represents not just to the physical or technical system that people interact with but also to the social and organisational system.

Three key domains of specialisation in ergonomics exist, as described on the IEA website, which represent deeper competencies in specific human attributes or characteristics of human interaction:

Cognitive ergonomics is concerned with mental processes, such as perception, memory, reasoning, and motor response, as they affect interactions among humans and other elements of a system. (Relevant topics include mental workload, decision-making, skilled performance, human-computer interaction, human reliability, work stress and training as these may relate to human-system design.)

Organizational ergonomics is concerned with the optimization of sociotechnical systems, including their organizational structures, policies, and processes.